UL 2021
Standard for Fixed and Location-Dedicated Electric Room Heaters

DETAILS
Edition Number:4SCC Approved:--
Edition Date:2015-09-30DOD Approved: --
Price Code:DANSI Approved: 2016-12-14
Type:ulstd

  • SCOPE

    1 Scope

    1.1 These requirements cover fixed and location-dedicated electric room heating equipment rated 600 volts or less to be employed in ordinary locations in accordance with the National Electrical Code, ANSI/NFPA 70.

    1.2 These requirements do not cover movable heaters, wall- or ceiling-hung heaters, baseboard heaters, duct heaters, central-heating furnaces, fan-coil units, panel- or cable-type radiant-heating equipment, electric boilers, or any other electric heating equipment or appliances that are covered in or as a part of separate, individual requirements.

  • TABLE OF CONTENTS
    Expand All

    • Cover
    • Transmittal
    • Table of Contents
      • Body
        • INTRODUCTION
          • 1 Scope
          • 2 Glossary
          • 3 Components
            • 3.1 General
            • 3.2 Attachment plugs, receptacles, connectors, and terminals
            • 3.3 Controls
            • 3.4 Cords, cables, and internal wiring
            • 3.5 Film-coated wire (magnet wire)
            • 3.6 Insulation systems
            • 3.7 Printed wiring boards
            • 3.8 Semiconductors and small electronic components
            • 3.9 Supplemental insulation, insulating bushings, and assembly aids
            • 3.10 Switches
            • 3.11 Transformers
          • 4 Units of Measurement
          • 5 References
          • 6 General
        • CONSTRUCTION
          • 7 Enclosure
          • 8 Parts Subject to Pressure
          • 9 Polymeric Materials
          • 10 Assembly
          • 11 Protection Against Corrosion
          • 12 Adjustment Stop
          • 13 Supply Connections
            • 13.1 Permanently connected appliances
            • 13.2 Cord-connected heaters
            • 13.3 Strain relief
            • 13.4 Pin terminals
            • 13.5 Bushings
            • 13.6 Pilot lights
          • 14 Current-Carrying Parts
          • 15 Internal Wiring
            • 15.1 General
            • 15.2 Protection of wiring
            • 15.3 Splices
            • 15.4 Separation of circuits
            • 15.5 Barriers
          • 16 Heating Elements
          • 17 Electrical Insulation
          • 18 Thermal Insulation
          • 19 Motors
            • 19.1 General
            • 19.2 Insulation systems
          • 20 Overcurrent Protection, General
          • 21 Overcurrent Protection, Motors and Motor Circuits
          • 22 Overcurrent Protection, High-Voltage Control Circuit Conductors
            • 22.1 Direct-connected high-voltage control circuit
            • 22.2 Tapped high-voltage control circuits
          • 23 Overcurrent Protection, Transformers
            • 23.1 High-voltage transformers
            • 23.2 Low-voltage transformers
          • 24 Temperature Limiting Means
          • 25 Alarms
          • 26 Receptacles and Transfer Switches
          • 27 Lampholders
          • 28 Switches
          • 29 Automatic Controls and Control Circuits
            • 29.1 General
            • 29.2 Terminals and actuating members of safety devices
          • 30 Spacings
          • 31 Grounding
          • 32 Guarding of Heating Elements
            • 32.1 General
            • 32.2 Panel-type heaters
            • 32.3 Floor heaters
        • PERFORMANCE
          • 33 General
          • 34 Power Input Test
          • 35 Leakage Current Test
          • 36 Normal Temperature Tests
          • 37 Conditions for Operation Tests
          • 38 Continuous Operation Test
          • 39 Terry Cloth Test Fabric
          • 40 Alarm Device Endurance Test
          • 41 Abnormal Operation Test
            • 41.1 General
            • 41.2 Abnormal motor temperature test
            • 41.3 Stalled fan
            • 41.4 Overvoltage test
            • 41.5 Tip over
            • 41.6 Vertical wall
            • 41.7 Terry cloth drape
            • 41.8 Litter
            • 41.9 Motor overload and stalled motor
            • 41.10 Wall-mounted heaters
            • 41.11 Floor insert heaters
            • 41.12 Ceiling-panel heaters
            • 41.13 Abnormal ambient test
          • 42 Endurance Test
          • 43 Short-Circuit Tests
          • 44 Overload Test – High-Voltage Transformers
          • 45 Burnout Test – High-Voltage Transformers
          • 46 Dielectric Voltage-Withstand Test
          • 47 Insulation Resistance Test
          • 48 Rain Test
          • 49 Static Load Test
          • 50 Stability of Cord-Connected, Floor-Supported Heaters
          • 51 Element Support Impact Tests
          • 52 Test for Permanence of Cord Tag
            • 52.1 General
            • 52.2 Test conditions
            • 52.3 Test method
          • 53 Protection Against Personal Injury Test
          • 54 Strength of Adjustment Stop Test
        • MANUFACTURING AND PRODUCTION TESTS
          • 55 Production-Line Dielectric Voltage-Withstand
          • 56 Production-Line Grounding Continuity
          • 57 Production-Line Tip Over
        • RATINGS
          • 58 Details
        • MARKINGS
          • 59 Details
          • 60 Instructions for Use and Care
            • 60.1 General
            • 60.2 Installation
            • 60.3 Important instructions
            • 60.4 Operation
            • 60.5 Maintenance
            • 60.6 Grounding instructions
            • 60.7 Heater carton information
    • CEILING INSERT AIR HEATERS WITH LAMPS